A conventional bed frame has two opposed side rails extending between a footboard and a headboard. These side rails may be made of any material but are most often made of wood. The side rails often have a flat horizontal flange extending inwardly from a vertical portion. In order to support the weight of a box spring and mattress, a plurality of transversely extending wooden or metal slats often were inserted between the side rails and rested on the horizontal flanges of the side rails. However, such transversely extending slats often warped, twisted outwardly or deflected under the weight of the box spring and mattress placed on top of the rails. As wider span-size beds such as a queen size bed which is 60" standard width or a king size bed which is 76" standard width became more popular, the wooden slats had to become longer and wider. The problem of twisting or torquing slats increased and in addition, the two opposed side rails tended to twist or turn outwardly as well due to the weight placed on the slats.
U.S. Pat. No. 4,080,674 discloses a center cross bar extending transversely of two opposed side bed rails which eliminates the need for transversely extending slats. The center cross bar is provided with two vertically adjustable supporting leg assemblies, each leg assembly having a vertically adjustable glide or foot at the lower end thereof. The glides contact a floor or other supporting surface to support the cross bar so as to prevent sagging of a box spring placed thereon and prevent any vertical deflection, horizontal deflection and twisting or torquing of the opposed side rails of the bed frame. Such a vertically adjustable supporting leg assembly incorporated into a cross bar enabled the two opposed bed rails or side rails to be pulled into a snug engagement with a box spring over a substantial portion of the length of the box spring in order to provide a firm support for the box spring along the bottom side and center portion of the box spring without having to utilize transversely extending removable slats.
U.S. Pat. No. 5,203,039 discloses a cross bar adjustable in length as well as height adapted to extend between two wooden side rails of a bed frame. The cross bar has multiple legs which are pivotally connected to the cross bar and capable of pivoting upwardly into a nesting relation with the cross bar for ease of packaging and/or shipping. The legs are also capable of being pivoted downwardly and secured in an erect position. In addition, this patent discloses a cross bar which is adjustable in length because the cross bar comprises two nestable sections each comprising an "L" shaped angle iron. The sections may be pulled apart to increase the length of the cross bar to fit a king size bed and an overlapped, nested portion of the sections secured with a clamp and thumb screw.
U.S. Pat. No. 5,502,852 discloses an extensible leg for a bed cross bar similar to the legs disclosed in U.S. Pat. No. 5,203,039. Like the legs disclosed in U.S. Pat. No. 5,203,039, the legs disclosed in U.S. Pat. No. 5,502,852 are adjustable in height and may be folded upwardly into a nested position inside the cross bar which has an L-shaped cross-sectional configuration. The leg disclosed in U.S. Pat. No. 5,502,852 has an integral bracket formed on the free end of the leg which is formed from the material of the leg and defines a substantially square opening which retains a plastic bushing and a threaded foot which can be raised and lowered in order to adjust the height of the cross bar relative to the supporting surface or floor. Thus, the leg disclosed in this patent is easier to fabricate and less expensive to make than the leg disclosed in U.S. Pat. No. 5,203,039.
However, in both the legs disclosed in U.S. Pat. Nos. 5,203,039 and 5,502,852, the height which the leg can be adjusted is limited by the height of the threaded stem of the foot member. The threads of the stem of the foot member are adapted to engage a plastic insert received within either the square opening of the integral bracket formed on the free end of the leg (U.S. Pat. No. 5,502,852) or a separate bracket secured to the leg with rivets (U.S. Pat. No. 5,203,039). Therefore, the vertical adjustment of the cross bar is limited to approximately the height of the threaded stem of the foot member which is typically only a few inches. Therefore, the height of the side rails above the supporting surface is limited because the bottom of the threaded foot members must engage the supporting surface in order to properly support a box spring placed on the bed frame.
Therefore, it has been one objective of the present invention to provide an adjustable bed frame center support assembly having legs which may be adjusted in height more than heretofore known legs having adjustable heights.
It has been a further objective of the present invention to provide a bed frame center support assembly comprising two cross support members and one center support member each having one or more vertically adjustable legs.
It has been a further objective of the present invention to provide a leg assembly which may be pivotally secured to a support member having an "L" shaped cross sectional configuration and nested therein, the leg assembly comprising multiple pieces which may be removably secured to one another.